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CLOUD COMPUTING - QUICK GUIDECLOUD COMPUTING - QUICK GUIDE

What is Cloud?The term Cloud refers to a Network or Internet. In other words, we can say that Cloud issomething which is present at remote location. Cloud can provide services over network i.e. onpublic networks or on private networks i.e. WAN, LAN or VPN.

Applications such as e-mail, web conferencing, customer relationshipmanagement CRM, all run in cloud.

What is Cloud Computing?Cloud Computing refers to manipulating, configuring, and accessing the applications online.It offers online data storage, infrastructure and application.

We need not to install a piece of software on our local PC and this is how, the cloudcomputing overcomes platform dependency issues. Hence, the Cloud Computingis making our business application mobile and collaborative.

Cloud Computing TechnologiesThere are certain technologies that are working behind the cloud computing platforms makingcloud computing flexible, reliable, usable. These technologies are listed below:

Virtualization

Service-Oriented Architecture SOA

Grid Computing

Utility Computing

Virtualization

Virtualization is a technique which allows to share single physical instance of an application orresource among multiple organizations or tenantscustomers. It does so by assigning a logical nameto a physical resource and providing a pointer to that physical resource when demanded.

The Multitenant architecture offers virtual isolation among the multiple tenants and therefore,the organizations can use and customize the application as though, they each has its own instancerunning.

Service-Oriented ArchitectureSOA

Service-Oriented Architecture helps to use applications as a service for other applicationsregardless type of vendor, product or technology. Therefore it is possible to exchange of databetween applications of different vendors without additional programming or making changes toservices.

cloud_computing-service_oriented_architecture

Grid ComputingGrid Computing refers to distributed computing in which a group computers from multiplelocations are connected with each other to achieve common objective. These computer resourcesare heterogeneous and geographically dispersed.

Grid Computing breaks complex task into smaller pieces. These smaller pieces are distributed toCPUs that reside within the grid.

Utility ComputingUtility computing is based on Pay per Use model. It offers computational resources on demandas a metered service. Cloud computing, grid computing, and managed IT services are based onthe concept of Utility computing

Cloud Computing ArchitectureThe Cloud Computing architecture comprises of many cloud components, each of them areloosely coupled. we can broadly divide the cloud architecture into two parts:

Front End

Back End

Each of the ends are connected through a network, usually via. Internet. The following diagramshows the graphical view of cloud computing architecture:

Front EndFront End refers to the client part of cloud computing system. It consist of interfaces andapplications that are required to access the cloud computing platforms. Eg. Web Browser

Back EndBack End refers to the cloud itself. It consist of all the resources required to provide cloudcomputing services. It comprises of huge data storage, virtual machines, securitymechanism, services, deployment models, servers etc.

Cloud Infrastructure ComponentsCloud infrastructure consist of servers, storage, network, management software, anddeployment software and platform virtualization.

HypervisorHypervisor is a firmware or low level program that acts as a Virtual Machine Manager. It allowsto share the single physical instance of cloud resources between several tenants.

Management SoftwareManagement Software helps to maintain and configure the infrastructure.

Deployment SoftwareDeployment software helps to deploy and integrate the application on the cloud.

NetworkNetwork is the key component of cloud infrastructure. It allows to connect cloud services over theinternet. It is also possible to deliver network as a utility over the internet i.e. the consumer cancustomize the network route and protocol.

ServerServer helps to compute the resource sharing and offer other services such as resource allocationand de allocation, monitoring resources, security etc.

StorageCloud uses distributed file system for storage purpose. If one of the storage resource fails then itcan be extracted from another one, which makes cloud computing more reliable.

Cloud Deployment ModelsFoloowing are the cloud deployment models:

Public Cloud Model

Private Cloud Model

Hybrid Cloud Model

Community Cloud Model

Public Cloud ModelThe Public Cloud Model allows systems and services to be easily accessible to general public.e.g. Google, Amazon, Microsoft offers cloud services via internet.

Benefits

Cost Effective

Reliability

Flexibility

Location Independence

Utility Style Costing

High Scalability

Disadvantages

Low Security

Less customizable

Private Cloud ModelThe Private Cloud allows systems and services to be accessible with in an organization. ThePrivate Cloud is operated only within a single organization. However, It may be managed internallyor by third-party.

Benefits

Here are the benefits of deploying cloud as private cloud model.

Higher Security and Privacy

More Control

Cost and energy efficiency

Disadvantages

Here are the disadvantages of using private cloud model:

Restricted Area

Inflexible Pricing

Limited Scalability

Additional Skills

Hybrid Cloud ModelThe Hybrid Cloud is mixture of public and private cloud. Non Critical activities are performedusing public cloud while the critical activities are performed using private cloud.

Benefits

Here are the benefits of deploying cloud as hybrid cloud model:

Scalability

Flexibility

Cost Efficiencies

Disadvantages

Here are the disadvantages of Hybrid Cloud Model:

Networking Issues

Security Compliance

Infrastructural Dependency

Community Cloud ModelThe Community Cloud allows system and services to be accessible by group of organizations. Itshares the infrastructure between several organizations from a specific community. It may bemanaged internally or by the third-party.

Benefits

Here are the benefits of deploying cloud as community cloud model:

Cost effective

Sharing Between Organizations

Security

Issues

Since all data is housed at one location, therefore one must be careful in storing data incommunity cloud because it might be accessible by others.

It is also challenging to allocate responsibilities of governance, security and cost.

Cloud Service ModelsFollowing are the cloud service models:

Infrastructure as a ServiceIaaS Model

Platform as a ServicePaaS Model

Software as a ServiceSaaS Model

Identity as a ServiceIDaaS Model

Network as a ServiceNaaS Model

Infrastructure as a ServiceIaaS

IaaS provides access to fundamental resources such as physical machines, virtual machines,virtual storage etc. Apart from these resource the IaaS also offers:

Virtual machine disk storage

Virtual local area network VLANs

Load balancers

IP addresses

Software bundles

All of the above resources are made available to end user via server virtualization. Moreover,these resources are accessed by the customers as if they own them.

Benefits

IaaS allows the cloud provider to freely locate the infrastructure over the internet in cost-effectivemanner. Some of the key benefits of IaaS are listed below:

Full Control of the computing resources through Administrative Access to VMs.

Flexible and Efficient renting of Computer Hardware.

Portability, Interoperability with Legacy Applications.

Issues

Here are the issues associated with IaaS:

Compatibility with Legacy Security Vulnerabilities

Virtual Machine Sprawl

Robustness of VM-level Isolation

Data Erase Practices

Characteristics

Here are the characteristics of IaaS service model:

Virtual machines with pre-installed software.

Virtual machines with pre-installed Operating Systems such as windows, Linux, and Solaris.

On-demand availability of resources.

Allows to store copies of particular data in different locations.

The computing resources can be easily scaled up and down.

Platform as a ServicePaaS

PaaS offers the run time environment for applications. It also offers development & deploymenttools, required to develop applications. PaaS has a feature of point-and-click tools that enablesnon-developers to create web applications.

The following diagram shows how PaaS offers an API and development tools to the developers andhow it helps the end user to access business applications.

Benefits

Following are the benefits of PaaS model:

Lower administrative overhead

Lower total cost of ownership

Scalable Solutions

More current system software

Issues

Like SaaS, PaaS also place significant burdens on consumer's browsers to maintain reliable andsecure connections to the provider systems. Therefore, PaaS shares many of the issues of SaaS.However, there are some specific issues associated with PaaS as listed below:

Lack of portability between PaaS clouds

Event Based Processor Scheduling

Security Engineering of PaaS applications

Software as a Service SaaSSoftware as a ServiceSaaS model allows to provide software applications as a service to the endusers. It refers to a software that is deployed on a hosted service and is accessible via internet.There are several SaaS applications. Some of them are listed below:

Billing and Invoicing System

Customer Relationship Management CRM applications

Help Desk Applications

Human Resource HR Solutions

Characteristics

Here are the characteristics of SaaS service model:

SaaS makes the software available over the internet.

The Software are maintained by the vendor rather than where they are running.

The license to the software may be subscription based or usage based. And it is billed onrecurring basis.

SaaS applications are cost effective since they do not require any maintenance at end userside.

They are available on demand.

They can be scaled up or down on demand.

They are automatically upgraded and updated.

SaaS offers share data model. Therefore multiple users can share single instance ofinfrastructure. It is not required to hard code the functionality for individual users.

All users are running same version of the software.

Benefits

Using SaaS has proved to be beneficial in term of scalability, efficiency, performance and muchmore. Some of the benefits are listed below:

Modest Software Tools

Efficient use of Software Licenses

Centralized Management & Data

Platfrom responsibilities managed by provider

Multitenant solutions.

Issues

There are several issues associated with SaaS. Some of them are listed below:

Browser based risks

Network dependence

Lack of portability between SaaS clouds

Identity as a ServiceIDaaS

Overview

Employees in a company require to login to system to perform various tasks. These systems maybe based on local server or cloud based. Following are the problems that an employee might face:

Remembering different username and password combinations for accessing multipleservers.

If an employee leaves the company, It's required to ensure that each of the user's accounthas been disabled. This increases workload on IT staff.

To solve above problems, a new technique emerged which is known as Identity as a Service IDaaS.

IDaaS offers management of identity information as a digital entity. This identity can be used duringelectronic transactions.

Identity

Identity refers to set of attributes associated with something and make it recognizable. All objectsmay have some same attributes but their identity can not be the same. This unique identity isassigned through unique identification attribute.

There are several identity services that have been deployed to validate servicessuch as validating web sites, transactions, transaction participants, client etc. Identityas a Service may include the following:

Directory Services

Federated Services

Registration

Authentication Services

Risk and Event monitoring

Single sign-on services

Identity and Profile management

Single Sign-On SSO

To solve the problem of using different username & password combination for different servers,companies now employ Single Sign-On software, which allows the user to login only one time andmanages the user's access to other systems.

SSO has single authentication server, managing multiple access to other systems, as shown in thefollowing diagram:

SSO working

There are several implementations of SSO. Here, we discuss the common working of SSO:

Following steps explain the working of Single Sign-On software:

1. User logs into the authentication server using a username and password.

2. The authentication server returns the user's ticket.

3. User sends the ticket to intranet server.

4. Intranet server sends the ticket to the authentication server.

5. Authentication server sends the user's security credentials for that server back to theintranet server.

If an employee leaves the company, then it just required to disable the user at theauthentication server, which in turn disable the user's access to all the systems.

Federated Identity ManagementFIDM

FIDM describes the technologies and protocols that enable a user to package security credentialsacross security domains. It uses Security Markup Language SAML to package a user's securitycredentials as shown in the following diagram:

OpenID

It offers users to login multiple websites with single account. Google, Yahoo!, Flickr, MySpace,WordPress.com are some of the companies that support OpenID.

Benefits

Increased site conversation rates.

Access to greater user profile content.

Fewer problems with lost passwords.

Ease of content integration into social networking sites.

Network as a ServiceNaaS

Overview

Networks as a Service allows us to access to network infrastructure directly and securely. NaaSmakes it possible to deploy custom routing protocols.

NaaS uses virtualized network infrastructure to provide network services to the consumer. It isthe responsibility of NaaS provider to maintain and manage the network resources, whichdecreases the workload from the consumer. Moreover, NaaS offers network as a utility.

NaaS is also based on pay-per-use model.

How NaaS is delivered?

To use NaaS model, the consumer is required to logon to the web portal, where he can get on lineAPI. Here, the consumer can customize the route.

In turn, consumer has to pay for the capacity used. It is also possible to turn off the capacity at anytime.

Mobile NaaS

Mobile NaaS offers more efficient and flexible control over mobile devices. It uses virtualization tosimplify the architecture to create more efficient processes.

Following diagram shows the Mobile NaaS service elements:

NaaS Benefits

NaaS offers a number of benefits, some of the are discussed below:

Independence

Analytics

Resilience

Ease of Adding new Service Elements

Isolation of customer traffic

Support Models

Cloud Management TasksCloud Management involves a number of tasks to be performed by the cloud provider to ensureefficient use of cloud resources. Here, we will discuss some of these tasks:

Audit System Backups

System's Data Flow Management

Ensuring no Vendor Lock-in

Provider's security procedures

Monitor Capacity Planning and Scaling Capabilities

Monitor Audit-Log Use

Solution testing and Validation

Cloud Data StorageCloud Storage is a service that allows to save data on offsite storage system managed by thirdparty and is made accessible by a web services API.

Storage DevicesStorage devices can be broadly classified into two categories:

Block Storage Devices

File Storage Devices

Block Storage Devices

Block Storage Devices offers the raw storage to the clients. This raw storage can be partitioned

to create volumes.

File Storage Devices

File Storage Devices offers storage to clients in form of files, maintaining its own file system. Thisstorage is in the form of Network Attached Storage NAS.

Cloud Storage ClassesCloud Storage can be broadly classified into two categories:

Unmanaged Cloud Storage

Managed Cloud Storage

Unmanaged Cloud Storage

Unmanaged Cloud Storage means that the storage is preconfigured for the consumer. Theconsumer can not format nor the consumer can install own file system or change drive properties.

Managed Cloud Storage

Managed Cloud Storage offers online storage space on demand. Managed cloud storage systempresents what appears to the user to be a raw disk that the user can partition and format.

Creating Cloud Storage SystemThe cloud storage system stores multiple copes of data on multiple servers and in multiplelocations. If one system fails then it only requires to change the pointer to stored object's location.

To aggregate storage assets into cloud storage systems, the cloud provider can use storagevirtualization software, StorageGRID. It creates a virtualization layer that fetches storage fromdifferent storage devices into a single management system. It can also manage data from CIFSand NFS file system over the Internet. The following diagram shows how SystemGRID virtualizesthe storage into storage clouds:

Virtual Storage ContainersVirtual storage containers offer high performance cloud storage systems. Logical Unit NumberLNU of device, files and other objects are created in virtual storage containers. Following diagramshows a virtual storage container, defining a cloud storage domain:

ChallengesStoring the data in cloud is not that simple task. Apart from its flexibility and convenience, it alsohas several challenges faced by the consumers. The consumers require ability to:

Provision additional storage on demand.

Know and restrict the physical location of the stored data.

Verify how data was erased?

Have access to a documented process for surely disposing of data storage hardware.

Administrator access control over data.

Virtualization ConceptCreating a virtual machine over existing operating system and hardware is referred as HardwareVirtualization. Virtual Machines provide an environment that is logically separated from theunderlying hardware.

The machine on which the virtual machine is created is known as host machine and virtualmachine is referred as a guest machine. This virtual machine is managed by a software orfirmware which is known as hypervisor.

HypervisorHypervisor is a firmware or low level program that acts as a Virtual Machine Manager. There aretwo types of hypervisor:

Type 1 hypervisor runs on bare system. LynxSecure, RTS Hypervisor, Oracle VM, Sun xVMServer, VirtualLogic VLX are examples of Type 1 hypervisor. The following diagram shows the

Type 1 hypervisor.

The type1 hypervisor does not have any host operating system because they areinstalled on a bare system.

Type 2 hypervisor is a software interface that emulates the devices with which a systemnormally interacts. Containers, KVM, Microsoft Hyper V, VMWare Fusion, Virtual Server2005 R2, Windows Virtual PC and VMWare workstation 6.0 are examples of Type 2hypervisor. The following diagram shows the Type 2 hypervisor.

Types of Hardware VirtualizationHere are the three types of hardware virtualization:

1. Full Virtualization

2. Emulation Virtualization

3. Paravirtualization

Full VirtualizationIn Full Virtualization, the underlying hardware is completely simulated. Guest software do notrequire any modification to run.

Emulation VirtualizationIn Emulation, the virtual machine simulates the hardware and hence become independent of theit. In this, the guest operating system does not require modification.

ParavirtualizationIn Paravirtualization, the hardware is not simulated. The guest software run their own isolateddomains.

VMware vSphere is highly developed infrastructure that offers a managementinfrastructure framework for virtualization. It virtualizes the system, storage andnetworking hardware.

Securing the CloudSecurity in cloud computing is a major concern. Data in cloud should be stored in encrypted form.To restrict client from direct accessing the shared data, proxy and brokerage services should beemployed.

Security PlanningBefore deploying a particular resource to cloud, one should need to analyze several attributesabout the resource such as:

Select which resources, he is going to move to cloud and analyze its sensitivity to risk.

Consider cloud service models such as IaaS, PaaS, and SaaS. These models requireconsumer to be responsible for security at different level of service.

Consider which cloud type such as public, private, community or hybrid.

Understand the cloud service provider's system that how data is transferred, where it isstored and how to move data into and out of cloud.

Mainly the risk in cloud deployment depends upon the service models and cloudtypes.

Understanding Security of Cloud

Security BoundariesA particular service model defines the boundary between the responsibilities of service providerand consumer. Cloud Security Alliance CSA stack model defines the boundaries between eachservice model and shows how different functional units relate to each other. The following diagramshows the CSA stack model:

Key points to CSA model:

IaaS is the most basic level of service with PaaS and SaaS next two above level of service.

Moving upwards each of the service inherits capabilities and security concerns of the modelbeneath.

IaaS provides the infrastructure, PaaS provides platfrom development environment and SaaSprovides operating environment.

IaaS has the least level of integrated functionalities and integrated security while SaaS hasthe most.

This model describes the security boundaries at which cloud service provider's responsibilityends and the consumer's responsibilities begin.

Any security mechanism below the security boundary must be built into the system andabove should me maintained by the consumer.

Although each service model has security mechanism but security needs alsodepends upon where these services are located, in private, public, hybrid orcommunity cloud.

Understanding Data SecuritySince all the data is transferred using internet, therefore, data security is of major concern incloud. Here are key mechanisms for protecting data mechanisms listed below:

Access Control

Auditing

Authentication

Authorization

All of the service model must should incorporate security mechanism operating in all abovementioned areas.

Isolated Access to DataSince data stored in the cloud can be accessed from anywhere, therefore, in order to protect thedata, we must have a mechanism to protect it from the client direct access.

Brokered Cloud Storage Access is one of the approach for isolating the storage in cloud. In thisapproach two services are created:

A broker with full access to storage but no access to client.

A proxy with no access to storage but access to both client and broker.

working of Brokered Cloud Storage Access systemWhen the client issue request to access data:

The client data request goes to proxy's external service interface.

The proxy forwards the request to the broker.

The broker requests the data from cloud storage system.

The cloud storage system returns the data to the broker.

The broker returns the data to proxy.

Finally the proxy sends the data to the client.

All of the above steps are shown in the following diagram:

EncryptionEncryption helps to protect data from being compromised. It protects data that is being transferredas well as data stored in the cloud. Although encryption helps to protect data from anyunauthorized access, it does not prevent from data loss.

Cloud Computing OperationsOverviewCloud computing operation refers to delivering superior cloud service. Today cloud computingoperations have become very popular and widely employed by many of the organizations justbecause, it allows to perform all business operations over the internet.

These operations can be performed using a web application or mobile based applications. Thereare a number of operations that are performed in cloud, some of them are shown in the followingdiagram:

Managing Cloud OperationsThere are several ways to manage day to day cloud operations, as shown in the following diagram:

Always employ right tools and resources to perform any function in the cloud.

Things should be done at right time and at right cost.

Selecting an appropriate resource is mandatory for operation management.

The process should be standardized and automated to avoid repetitive tasks.

Using efficient process will eliminate the waste and redundancy.

One should maintain the quality of service to avoid re-work later.

Cloud ApplicationsCloud Computing has its applications in almost all the fields such as business, entertainment,data storage, social networking, management, entertainment, education, art and globalpositioning system etc. Some of the widely famous cloud computing applications are discusseshere in this tutorial:

Business ApplicationsCloud computing has made business more collaborative and easy by incorporating various appssuch as MailChimp, Chatter, Google Apps for business, and Quickbooks.

SN Application Description

1 MailChimpIt offers an email publishing platfrom. It is widely employed by the businesses to designand send their email campaigns.

2 ChatterChatter app helps the employee to share important information about organization inreal time. One can get the instant feed regarding any issue.

3 Google Apps for BusinessGoogle offers creating text documents, spreadsheets, presentations etc. on GoogleDocs which allows the business users to share them in collaborating manner.

4 QuickbooksIt offers online accounting solutions for a business. It helps in monitoring cash flow,creating VAT returns and creating business reports.

Data Storage and BackupBox.com, Mozy, Joukuu are the applications, offering data storage and backup services in cloud.

SN Application Description

1 Box.comBox.com offers drag and drop service for files. It just required to drop the files into Boxand access from anywhere.

2 MozyMozy offers online backup service for files during a data loss.

3 JoukuuJoukuu is a web based interface. It allows to display a single list of contents for files storedto Google Docs, Box.net and Dropbox.

Management ApplicationsThere are apps available for management task such as time tracking, organizing notes.Applications performing such tasks are discussed below:

SN Application Description

1 TogglIt helps in tracking time period assigned to a particular project.

2 EvernoteEvernote is an application that organizes the sticky notes and even can read the text fromimages which helps the user to locate the notes easily.

3 OutrightIt is an accounting app. It helps to track income, expenses, profits and losses in real time.

Social ApplicationsThere are several social networking services providing websites such as Facebook, Twitter etc.

SN Application Description

1 FacebookFacebook offer social networking service. One can share photos, videos, files, status andmuch more.

2 TwitterTwitter helps to interact directly with the public. Once can follow any celebrity,organization and any person who is on twitter and can have latest updates regarding thesame.

Entertainment Applications

SN Application Description

1 Audiobox.fmIt offers streaming service i.e. music can be stored online and can be played from cloud

using service's own media player.

Art Applications

SN Application Description

1 MooIt offers art services such as designing and printing business cards, poscards andminicards.

Cloud ProvidersVarious Cloud Computing platforms are available today. The following table contains the popularCloud Computing platforms:

SN Platforms Description

1 Salesforce.comThis is a Force.com development platfrom. This provide a simple user interface and letsusers log in, build an app and push it in the cloud.

2 AppistryThe Appistry's CloudQ platform is efficient in delivering a run-time application platform.This platform is very useful to create scalable and service oriented applications.

3 AppScaleThe AppScale is an open source platform for Google App Engine applications.

4 AT&TThe AT&T allows access to virtual servers and manages the virtualization AT&T The AT&Tallows access to virtual servers and manages the virtualization infrastructure. Thisvirtualization infrastructure includes network, server and storage.

5 Engine YardThe Engine Yard is a Rails Application cloud computing platform.

6 EnomalyEnomaly's provides the Infrastructure-as-a-Service platform.

7 FlexiScaleThe FlexiScale offers a cloud computing platform that allows flexible, scalable andautomated cloud infrastructure.

8 GCloud3The GCloud3 offers private cloud solution in its gPlatform.

9 GizmoxThe Gizmox Visual WebGUI platfrom is best suited for developing new web apps andmodernize the legacy apps based on ASP.net, DHTML etc.

10 GoGridThe GoGrid platform allows the users to deploy web and database cloud services.

11 GoogleThe Google's App Engine, let the users build, run and maintain their applications onGoogle's infrastructure.

12 LongJumpThe LongJump offers a Business Application Platform, a platform-as-a-Service PaaS.

13 MicrosoftThe Microsoft's Windows Azure is a cloud computing platform, offering an environment tocreate cloud apps and services.

14 OrangeScapeOrangeScape is offers a Platform-as-a-Service Paas for non programmers. Building an appis as easy as spreadsheet.

15 RackSpaceThe RackSpace provide servers-on-demand via a cloud-driven platfrom of virtualizedservers.

16 Amazon EC2The Amazon EC2 ElasticComputeCloud lets the users configure and control computingresources while running them on Amazon's environment.

Cloud Computing ChallengesCloud computing, an emergence technology, have placed many challenges in different aspects.Some of these are shown in the following diagram:

Security & PrivacySecurity and Privacy of information is the biggest challenge to cloud computing. To get out ofsecurity and privacy issues can be over come by employing encryption, security hardware andsecurity applications.

PortabilityThis is another challenge to cloud computing that applications should easily be migrated form onecloud provider to another. There should not be vendor-lock in. However, it is not yet made possiblebecause each of the cloud provider use different standard languages for their platforms.

InteroperabilityApplication on one platform should be able to incorporate services from other platfrom. It is madepossible via web services. But this writing such web services is very complex.

Computing PerformanceTo deliver data intensive applications on cloud requires high network bandwidth which result inhigh cost. If done at low bandwidth, then it does not meet the required computing performance of

cloud application.

Reliability and AvailabilityIt is necessary for cloud systems to be reliable and robust because most of the business are nowbecoming dependent on services provided by third party.

Mobile Cloud ComputingCloud Computing offers such smartphones that have rich internet media experience and requireless processing, less power. In term of Mobile Cloud Computing, processing is done in cloud, data isstored in cloud. And the mobile devices serve as a media for display.

Today smartphones are employed with rich cloud services by integrating applications thatconsume web services. These web services are deployed in cloud.

There are several Smartphone operating systems available such as Google's Android, Apple'siOS, RIM BlackBerry, Symbian, and Windows Mobile Phone. Each of these platform supportthird party applications that are deployed in cloud.

ArchitectureMCC includes four types of cloud resources:

Distant mobile cloud

Distant immobile cloud

Proximate mobile computing entities

Proximate immobile computing entities

Hybrid

The following diagram shows the framework for mobile cloud computing architecture:

IssuesDespite of having significant development in field of mobile computing, there still exists manyissues:

Emergency efficient transmissionThere should be a frequent transmission of information between cloud and the mobile devices.

Architectural IssuesMobile cloud computing is required to make architectural neutral because of heterogeneousenvironment.

Live VM migrationIt is challenging to migrate an application which is resource-intensive to cloud and to execute itvia. Virtual Machine .

Mobile Communication CongestionDue to continuous increase demand for mobile cloud services, the workload to enable smoothcommunication between cloud and mobile devices has been increased.

Security and PrivacyThis is one of the major issue because mobile users share their personal information over thecloud.Loading [MathJax]/jax/output/HTML-CSS/fonts/TeX/fontdata.js